I have used 97 RON and I don't think it made any difference. Except it was really expensive. The fuel economy might have been better but it costs more so therefore you get less miles for your money.
Standard unleaded is fine, but given that I only get about 8 gallons per fill, the extra GBP1.50 for Optimax is so little I nearly always fill with it....Garry said:What experiences have MINI owners had with the different octanes for petrol?
Does the higher octane 97 RON improve performance and fuel economy?
Can you run Shell Optimax 100 RON in the MINI?
Which brand of petrol is 'best' or doesn't that matter?
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Shell's Optimax rings alarm bells in my head regarding the debarcle with Formula Shell in the late 80's. Didn't that ruin the valve seals on Vauxhall engines amongst others. I know it's 10+ years on but does anybody know what Shell has done to avoid simular problem. At the moment I turn various shades of red whenever my gilrfriend says "the only Super Unleaded I could find was Shell Optimax, but don't worry I filled up the tank for you".Johnboy said:
Standard unleaded is fine, but given that I only get about 8 gallons per fill, the extra GBP1.50 for Optimax is so little I nearly always fill with it....
It's supposed to clean your valves too. I intend on doing a 1 in 3 of Optimax at the very least, just in case it really goes keep the valves clean, and just in case that makes some sort of difference
I find my car starts better and is smoother at low revs with Optimax. There is a very marginal improvement in performance too.
One of the other threads suggested the diff. would be greater in hotter countries/summer time because detonation is less likely to occur with higher Octane fuel, so the ECU would be able to advance the timing that bit more, relative to 97RON. Roll on Summer - Now where's that sunroof switch gone
Incidentally what's that horrid 91RON stuff that comes as the standard fuel in N.Z... Total pants! It should be relegated to use by moped riders and dumper trucks!
The 91RON is the regular unleaded in Australia as well. From memory the highest octane is 95RON - called Premium Unleaded. The cars run OK on 91 but if you have a reasonable car you need to use the higher octane.Johnboy said:
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Incidentally what's that horrid 91RON stuff that comes as the standard fuel in N.Z... Total pants! It should be relegated to use by moped riders and dumper trucks!
Yeah, at 300 miles, my engine (in relative terms) was "as tight as a gnat's ass"! It started to noticably loosen up at about 600 plus and now after 3k seems to be bedded in nicely....Garry said:
The 91RON is the regular unleaded in Australia as well. From memory the highest octane is 95RON - called Premium Unleaded. The cars run OK on 91 but if you have a reasonable car you need to use the higher octane.
I have filled up with Shell Optimax 98RON in my 300 mile old MINI. Seems OK, but I haven't noticed any improvement in power or economy. I figure that the car is too new and needs to be run in for a few thousand miles.
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Blimey, you're treading dangerously aren't you? I start to panic at 30 miles on the computer but maybe its more conservative than I thought. I have heard that letting a tank go right down to empty can wreak the catalyst.Alex said:I too have used Shell Optimax......0 miles on trip computer for ten miles